The calcaneus is the name of the bone in a person's foot which is more generally known as the heel bone. Fractures of the calcaneus generally represent approximately two percent (2%) of all bone fractures, and can range from mild to severe. In moderate to severe cases where pieces of the calcaneus have separated, surgery is normally required to attempt to restore the heel as close as possible to its original condition.
In most cases the calcaneal fractures are primarily compression fractures and the primary problems that physicians need to address in treatment arise from a loss of height and width of the calcaneus, with some displacement of the subtalar joint. The subtalar joint is the complex joint below the ankle.
The treatment generally involves a two phase surgical correction or procedure. The correction generally includes two phases because the initial injury causes soft tissue inflammation or swelling and the calcaneus bone or bone pieces are not located where desired and the site of the operation is not ready for the final surgery. The first phase of the treatment will typically involve the implant or insertion of a calcaneal pin transversely through the calcaneal such that a first end and a second end of the calcaneal pin protrude on opposite sides of the patient's foot. During the initial surgery an external fixation device is placed on the leg and foot and attached to the calcaneal pin to restore length and height to the calcaneus bone that may have been lost as a result of the injury (such as a compression fracture).
The external fixation device is typically fixed to the patient's leg by placing pins in the front of the tibia combined with a transverse calcaneal pin inserted or implanted through the calcaneus. Once the calcaneal pin is placed or transversely fixed in the calcaneal, the calcaneal pin may be manipulated to bring the fracture and calcaneal into the desired state or condition. This may involve manually pulling and/or otherwise manipulating the calcaneal pin to place the fracture and calcaneal in a desired position (such as to a position of anatomical reduction).
The prior art external fixation devices normally include “clips” or attachment mechanisms that attach to the first end and second end of the transversely inserted calcaneal pin and tightened on the top bottom and sides to hold the calcaneal pin and consequently the calcaneal in a desired corrected position. A known problem with setting or fixing the calcaneal in the desired corrected position is that it is a very subjective procedure and it is difficult to consistently locate or fix the calcaneal in the desired or optimal position.
It should be noted that setting or fixing the calcaneal into this initial fixed position is subjectively accomplished in contemplation of a second surgery to repair the calcaneal or pieces thereof—preferably as close to the pre-injury position as possible.
Once the first phase of treatment, i.e. the first surgery and initial fixation is completed and the patient is out of the operating room, there is currently no practical way to adjust the level of correction imparted on the calcaneal without performing an additional surgery. When there is not any way to adjust the correction imposed on the calcaneal after the first surgery but before the second surgery, the outcome or success from the second surgery may be limited by the subjective placement or fixation performed in the first surgery. The subjective and imprecise nature of the fixation of the calcaneal during the first surgery combined with the inability to make any changes leading up to the second surgery, can negatively affect the outcome of the treatment of the patient during the second surgery. Again the second surgery portion of the treatment is when the patient's heel is opened up and the restorative work to the calcaneal is being done.
While there have been prior types of external fixation devices, the prior devices have been very complex and difficult to use, such that they are rarely or not often used.
While the goal of fixing the calcaneal with the external fixation device in the first surgery is to fix the patient's calcaneal in the optimal position, this does not always occur. The second surgery phase of the treatment typically involves opening the patient's foot up in the position it was fixed in during the first surgery and then for example placing a plate and/or screws onto the calcaneal bone or bone pieces to hold the fracture in place (presumably in the same position it was fixed during the first surgery). It is therefore evident how important the original fixation of the calcaneal is during the first surgery, to the overall outcome for the patient.
The second surgery phase of the patient treatment is also complicated or impeded by physical presence of the framework fixing the calcaneal during the second surgery.
The lateral portion of the frame of current devices is directly in front of the surgical site where the patient's foot would typically be opened. This requires the surgeon to perform a complex surgery while working around a portion of the external fixation device. The prior art devices therefore impose an undesirable obstacle to the second surgery portion of the treatment, further complicating the treatment.
It is therefore an object of embodiments of this invention to provide a calcaneal fixation device which reduces or eliminates the problems associated with possibly fixing the calcaneal in a less than desired position for the optimal outcome for the patient treatment.
An advantage of embodiments of this invention is that it provides an adjustable calcaneal fixation device which allows adjustment or changes to the fixed position of the patient's calcaneal after the first surgery part of the treatment and leading up to the second surgery portion of the treatment. Embodiments of this adjustable calcaneal fixation device further may provide complete adjustability in all planes both in the operation room during the first surgery phase, and after the first surgery. The correction provided by embodiments of this invention are therefore very consistent and reproducible. It also allows the surgeon to make adjustment after the surgery, in any plane that is desired, at any time in the postoperative period.
Embodiments of this invention further provide for dynamic distraction (versus only providing for static distraction) while allowing the patients heel to be moved gradually back into place while fixed before the second surgery.
It is also an object of embodiments of this invention to provide a calcaneal fixation device which does not pose an obstruction to the surgeon's access to the patient's heel during the second surgery.
An advantage of embodiments of this invention is that it may provide an external fixation device in which the framework is only located on one side of the patient's calcaneal during the surgery. This may be provided by providing a framework which includes structure on both sides of the calcaneal with the structure on the surgery side being removable for the surgery; or by providing a framework which only includes structure on the non-surgical side of the patient's calcaneus.
Despite the longstanding and recognized need for external calcaneal fixation devices which provide solutions to one or more of the objects of this invention, none until this invention have heretofore been developed.
Other objects, features, and advantages of this invention will appear from the specification, claims, and accompanying drawings which form a part hereof. In carrying out the objects of this invention, it is to be understood that its essential features are susceptible to change in design and structural arrangement, with only one practical and preferred embodiment being illustrated in the accompanying drawings, as required.